19953195440 has 20 divisors (see below), whose sum is σ = 46391179584. Its totient is φ = 7981278144.

The previous prime is 19953195433. The next prime is 19953195473. The reversal of 19953195440 is 4459135991.

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124707392 + ... + 124707551.

Almost surely, 2^19953195440 is an apocalyptic number.

19953195440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19953195440 is an abundant number, since it is smaller than the sum of its proper divisors (26437984144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19953195440 is a wasteful number, since it uses less digits than its factorization.

19953195440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249414956 (or 249414950 counting only the distinct ones).

The product of its (nonzero) digits is 874800, while the sum is 50.

The spelling of 19953195440 in words is "nineteen billion, nine hundred fifty-three million, one hundred ninety-five thousand, four hundred forty".